Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description carries the full burden and discloses the key behavioral traits: immediate deletion of the channel, both keys, and all stored messages, plus the effect on the other side's next fetch. It does not mention authentication requirements or irreversibility explicitly, but the destructive and cross-party consequences are well covered.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two short, front-loaded sentences with no wasted words. The most important consequence (deletion) is stated immediately.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a single-parameter, annotation-free tool with no output schema, the description covers what the tool does, who can trigger it, what is destroyed, and how the other side is affected. Nothing essential for correct invocation is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The schema has 100% description coverage for the single 'key' parameter, so the baseline is 3. The description adds only the context that either side can close, without further detail on the key's format or source.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description states a specific verb ('close') and resource ('channel'), and adds the destructive consequence ('deletes the channel, both keys, and every stored message'). This clearly distinguishes it from siblings like channel_open, channel_join, channel_fetch, and channel_send.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

It notes that 'Either side can close,' which is a useful usage constraint, but it does not say when to close versus alternatives or when not to close. Usage is implied rather than explicitly guided.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.